[7.851][BUG][FIXED] Repeated SQL error entries in system log

SQL errors in system logs; generated every hour at xx:50. Screenshot attached

Astaro Beta Report
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Version: 7.851
Type: BUG
State: MERGED/FIXED
Reporter: Billybob
Contributor:  
MantisID: 12254
Target version: 7.865
Fixed in version: 7.865
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